Drought severity assessments in the Arjunanadhi and Kousiganadhi subbasins of Tamil Nadu, India: a meteorological perspective

Tamil Nadu is experiencing a drought that is driving large-scale migration for alternative livelihoods, increasing stress and unsanitary conditions, and causing social unrest. In the food and agriculture sectors, droughts are more severe. It is stated in the detailed project report of the Irrigated Agriculture Modernization and Water-Bodies Restoration and Management (IAMWARM) that the Arjunanadhi subbasin generally has a very high temperature and that drought occurs once every 5 years in semi-arid regions in the tropical climate. Tamilnadu's Drought Prone Areas Programme (DPAP) lists 80 blocks in several districts. Furthermore, it contains the Virudhunagar district and the blocks Virudhunagar, Sivakasi, Sattur, Aruppukottai, and Kariyapatti. These two subbasins include the above-mentioned blocks of Virudhunagar and Madurai districts. Therefore, an attempt was made to study this area, and the drought was analysed in a meteorological context by using the Drought Severity Index methods of the Indian Meteorological Department (IMD) and the Standardized Precipitation Index (SPI). Although there are some emerging concerns, the assessment of meteorological drought severity was based on the IMD method and the SPI method using precipitation data. Based on The IMD's method, it has been found that most blocks of the subbasin are drought-prone, and almost all of them experienced drought during the summer, southwest monsoon (SWM), and northeast monsoon (NEM) in 2013. According to the SPI, the blocks have experienced near-normal conditions in 1985, 1999, and 2013. It seems that the drought proneness continues and increases in consecutive years in the subbasin. Based on these findings, water resource management activities and drought mitigation strategies will be proposed in the subbasins. This study will provide useful information for preparing drought preparedness plans and mitigation strategies for the basins and will benefit the government and agencies involved in drought relief measures.

Automated summary

Tamil Nadu is currently experiencing a severe drought, leading to large-scale migration, increased stress, and unsanitary conditions. This study analyzes the severity of the drought in a meteorological context and proposes water resource management and drought mitigation strategies. The findings of this study will provide valuable information for preparing drought preparedness plans and relief measures, benefiting the government and agencies involved.